Island Press

Island Press is a nonprofit, environmental publisher based in Washington, D.C., United States, that specializes in natural history, ecology, conservation, and the built environment. Established in 1978, Island Press generates about half of its revenue through sales and half through donations by organizations and individuals.

From the Wikipedia article “Island Press”, licensed under CC BY-SA 4.0.

Large trade publishers generally accept manuscripts only through literary agents, while many independent and small presses accept direct submissions during reading periods. Before submitting anywhere, read the publisher's current guidelines, study recent books on its list, and never pay a reading or publishing fee to a traditional publisher.